Method and apparatus for turning the path of continuous webs collated in register



Jan. 17, 1967 w. F. HUCK 3,298,581

METHOD AND APPARATUS FOR TURNING THE PATH 0F CONTINUOUS WEBS GOLLA'IED IN REGISTER Filed June 23, 1965 2 Sheets-$heet 1 INVENTOR WILLIAM F. HUCK ATTARNE Y W. F. HUCK ATUS FOR TURN 3,298,581 ING THE PATH 0F CONTINUOUS WEBS COLLATED IN REGISTER 1 2 Sheets-Sheet 2 m P P A D N A D 0 "n T E 7 6 9 1 7 1 J Filed June 25, 1965 INVENTOR WILLIAM F. HUCK 1 ORNE Y United States Patent 7 3,298,531 METHOD AND APPARATUS FOR TURNING THE PATH F CONTINUOUS WEBS CGLLATED IN REGISTER William F. Huck, 81 Greenway Terrace, Forest Hills, N.Y. 11375 Filed June 23, 1965, Ser. No. 466,341

, 17 Claims. (Cl. 226-2) This invention relates generally to web processing machines in which a web group composed of a multiplicity of continuous patterned flexible webs superimposed in register is continuously drawn, under continuous tension, through a path having an arcuate portion, and is par ticularly directed to improved cylinders for guiding the web group in such arcuate portion of the path.

When a web group composed of a multiplicty of continuous, superimposed flexible web-s is drawn, under continuous tension, through a path having an arcuate portion, the individual webs at the outside of the arcuate portion of the path tend to travel greater distances than the individual webs disposed at the inside of the arcuate portion of the path. When the arcuate portion of the path of the web group is defined by a smooth cylindrical surface on a roller or cylinder, as has been the usual practice, the tendency of the individual webs to travel different distances causes an increase in the tension in the outer webs, leading to possible breakage of the latter, whereas the inner webs become loose and wrinkling thereof results. Where the webs of the group are patterned, for example, printed, perforated or embossed, and are superimposed in register in the group, the tightening of the outer webs and the loosening of the inner webs in the arcuate portion of the path introduces misregister of the patterns of the several webs. Furthermore, loosening of the inner webs in the arcuate portion of the path makes it difficult to maintain adequate tension in such webs in the run ofthe web group leading to the arcuate portion of the path whereb'y loops form and lateral wandering occurs in the inner webs at such run. The foregoing difficulties are accentuated by increasing the number of webs in the web group and by increasing the speed at which the web group is drawn through its path in the processing machine.

Accordingly, it is an object of this invention to provide means, in a web processing machine, by which a web group composed of a multiplicity of continuous patterned flexible webs superimposed in register and being drawn continuously under tension through a path having an arcuate portion, can be guided in such arcuate portion of the path without introducing misregister of the patterns of the several webs or wrinkling of the inner webs, and without adversely affecting the maintenance of adequate tension in all of the webs, particularly in the run of the web group leading to the arcuate portion of the path.

A more specific object is to provide a rotary cylinder peripherally defining an arcuate portion of the path of the web group in a web processing machine, and which is constructed and arranged to cause frictional resistance to relative longitudinal sliding of the several webs of the group at transversely extending regions spaced along the web group in the arcuate portion of the path, and permitting bowing of the inner Webs of the group between such regions.

In accordance with an important aspect of this invention, a rotary cylinder peripherally engaging a web group in a web processing machine and defining an arcuate portion of a path through which the web group is drawn under continuous tension, has its periphery defined by ridge elements spaced apart circumferentially and extending axially 0n the cylinder and engaging the innermost web of the group, such ridge elements present ing web-engaging crests sufiiciently narrow to localize the pressure of the web group bearing against them so that the friction resulting between the Webs will keep the webs from slipping longitudinally relative to one another in the regions of the crests; and the periphery of the cylinder further comprises, between the ridge elements, axial recesses which are sufliciently wide and deep to permit inward bowing of portions of the inner webs of the web group between the regions of the crests of the ridge elements.

The ridge elements of the rotary cylinder in accordance with this invention may be constituted by axial ribs projecting radially outward from the surface of a cylindrical body and being formed integrally with the latter or suitably secured thereto, with such ribs being of triangular, rectangular or arcuate cross-section so as to present the necessary narrow web-engaging crests. Alternatively, the ridge elements may be in the form of small diameter rollers extending parallel to the axis of the cylinder and being spaced apart around the circumference of the latter to define the narrow web-engaging crests at the sides of the rollers facing away from the axis of the cylinder, and further to define the axial recesses, into which the inner webs may bow, at the gaps between adjacent rollers.

The rotary cylinder for guiding a web group in a web processing machine in accordance with this invention may be rotated by its peripheral engagement with the web group at the arcuate portion of the path through which the web group is continuously drawn, or the rotary cylinder may be positively driven. Where the ridge elements of the rotary cylinder are constituted by rollers, the latter are preferably mounted so as to be freely rotatable about their individual axes and, in that case, the rotary cylinder is positively driven at a peripheral speed which is different from the speed of movement of the web group in the arcuate portion of the path, whereby the rollers will roll relative to the innermost web of the web group in the arcuate portion of the path for smoothing any creases, bulges or other irregularities present in the individual webs or that might be otherwise formed therein by engagement with the ridge elements of the cylinder.

Rotary cylinders provided in web processing machines in accordance with this invention may merely function to guide the web group in arcuate portions of the path of travel of the web group through the machine, or such cylinders may be included in tension or register control devices, in drive means by which the web group is drawn through its path, or in means by which the web group is cut, perforated or otherwise processed in the machine.

The above, and other objects, features and advantages of this invention, will be apparent in the following detailed description of illustrative embodiments thereof which is to be read in connection with the accompanying drawings forming a part hereof, and wherein:

FIG. 1 is a schematic side elevational view showin rotary cylinders in accordance with one embodiment of this invention for guiding and propel-ling a webgroup in arcuate portions of a path of travel in a Web processing machine;

FIG. 2 is a fragmentary enlarged view illustrating the action of a rotary cylinder of HG. 1 on the web group;

FIG. 3 is a fragmentary enlarged view of a section of a rotary cylinder in accordance with another embodiment of this invention;

FIG. 4 is a view similar to that of FIG. 2, but showing still another embodiment of the invention;

FIG. 5 is a schematic side elevational view, partly broken away and in section, showing a web processing machine having a rotary cylinder in accordance with still another embodiment of this invention and which forms part of the means by which the web group is driven and processed;

FIG. 6 is an enlarged detail view of a portion of the rotary cylinder of FIG. and

FIG. 7 is a fragmentary sectional view in an axial plane of a rotary cylinder embodying this invention, and showing the relationship of the cylinder to a web group guided thereby when the web group is constituted by folded webs or ribbons.

Referring in detail to FIG. 1 of the drawings, the invention is there shown embodied in rotary cylinders 10, 10 and 10" of a web processing machine 11 for continuously guiding and drawing a web group G composed of a multiplicity of superimposed, continuous flexible webs W under continuous tension through a path having arcuate portions defined by the peripheries of cylinders 10, 10 and 10". The continuous webs W of relatively thin material, such as, paper, cardboard, cloth, plastic, metal foil or the like, are preferably patterned, for example, printed, perforated or embossed, and are brought together or collated at the periphery of cylinder 11 with the patterns of the individual webs composing the group G in register with respect to each other.

It will be apparent that, in moving through an arcuate portion of the path of travel of web group G in machine 11, the outermost web W (FIG. 2), that is, the individual web at the outside of the arcuate portion of the path, will tend to travel a greater distance than the inner webs W that is, the webs disposed between the periphery of cylinder 1t) and the outermost web W If the web group is guided in an arcuate portion of its path by a smooth cylindrical surface, as in conventional web processing machines, the tendency of the individual webs to travel different distances in the arcuate portion of the path causes wrinkling of the inner webs W, against such smooth cylindrical surface, excessive tightening or tensioning of the outermost web W which may result in breakage thereof, and the introduction of misregister between the patterns ofthe several webs. Further, by reason of the loosening and wrinkling of the inner webs in the arcuate portion of the path, difliculty is experienced in maintaining adequate tension in such webs. at the run of the web group leading to the cylinder with the result that loops form in the inner webs and lateral wandering occurs.

In accordance with this invention, the above consequences of the tendency of the several webs composing the web group G to travel. different distances in the arcuate portions of the path of travel of the web group through the machine 11, are avoided by constructing each of rotary cylinders 10, 10' and 10" so as to have its periphery defined by ridge elements 14 which are spaced apart circum-- ridge elements 14, axial recesses 16 which are sufiiciently wide, preferably at least three times the width of the webengaging crests 15, and also sufliciently deep to permit inward bowing of portions of the inner webs W between the regions of the crests 15, as hereinafter described in detail.

The cylinder 10 may be suitably journalled, at its oppo- 7 site ends, in side frames 17 of the Web processing machine for rotation about a fixed axis, as shown on FIG. 1. Al-

887, or when employed in web register controls of the kind disclosed in US. Patent No. 3,097,844.

As shown on FIGS. 1 and 2, the ridge elements 14 may be constituted by axial ribs projecting radially outward from the cylindrical outer surface 18 of the body 19 of the cylinder, and which are formed integral with such body. The axial ribs constituting ridge elements 14 may be of triangular cross-section, as shown, or have rectangular, semi-circular or other cross-sections so long as the same are dimesnioned to present the necessary narrow crests 15 for engagement with the inner-most web of the web group.

Further, as shown in FIG. 3, the ridge elements14a may be formed separately from the body 1% of the cylinder, and removably attached to body 19a, as by bolts 20. This embodiment of the invention, which facilitates, and reduces the cost of manufacture of the cylinder for guiding a web group, has the furtheradvantage of permitting the replacement of any one of the ridge elements 14a in the event of damage thereto. A particularly convenient configuration for each removable ridge element 14a is that of an angle member, as shown, in which case one leg thereof is secured to the outer surface 18a of cylindrical body and the other leg of the angle member projects radially outward from surface 18a and presents the desired narrow, web-engaging crest 15a at its outer edge. Further, the recesses 16a into which the inner webs may how are defined between the outwardly projecting legs of the adjacent angle members.

When the ridge elements 14 or 14a are fixed at the periphery of the cylinder for guiding a web group in an arcuate portion of its path, as in the above described embodiments of the invention, the cylinder may be merely free to be rotated by its peripheral engagement with the web group being drawn continuously through the web processing machine, or the cylinder 10 may be positively rotated at a peripheral speed equal to the linear speed of movement of the web group by the driving cylinder 10 or other drive means For example, as shown on FIG. 1, the cylinder 10 may be positively driven through a belt and pulley transmission 21 connected, as by spur gearing 22, with a main drive shaft 23, and the driving cylinder 10 may be driven through a belt and pulley transmission 24 from that same main drive shaft. The web group G is guided by cylinder .10" so as to have a substantial wrap on driving cylinder 10. In order to permit adjustment of the wrap of web group G on cylinder 10 for ensuring positive drive of the web group by that cylinder, guiding cylinder 10 may be rotatably mounted between the ends of arms 25 which are rockable about the axis of cylinder 11) by adjustment of a screw 25a rotatably supported by a fixed bracket 25b and extending threadably through a nut member 250 pivotally connected to arms 25. 8

With particular reference to FIG. 2, it will be seen that, as the Web group enters the arcuate portion of its path defined by the periphery of cylinder 10, a ridge element 14, at the position A on the periphery of the cylinder, engages the innermost web and, by reason of the narrow crest 15 of ridge element 14, the pressure of the tensioned web group against the ridge element is localized at the region of the crest. The localized pressure results in friction between the several webs sufficient to keep the webs from slipping longitudinally relative to one an other in the region of the crest 15. During movement of a ridge element 14 from the position A, where it first engages the web group, to position B which is spaced from the position A by the circumferential distance between the crests 15 of adjacent ridge elements, the length L of the web group extending between the regions of the crests 15 of the ridge elements at positions A and B is angularly deflected relative to the following length of the web group. By reason of the thickness of the web group and the angular deflection thereof, the outer web W tends to travel a greater distance than the inner webs W However, since relative longitudinal slipping of the webs in the regions of the crests 15 is prevented by the friction between the webs resulting from the localized that purpose.

pressure'of'the web group bearing against the crests, the

tendency of the individual webs totravel different distances merely causes the .inner webs W, to 'bow inwardly in the recess 16 which is sufiiciently wide and deep for path of'travel of the web group defined by the periphery of cylinder 10, the several webs'are held against longiweb group, the length or run of the web group in advance of the ridge element moving .past position .C is angularly deflected relative to the following length L of the web group in the direction to take up the slack of the bowed-inner webs W in length L Since relative longitudinal sliding or shifting of the several webs at the regions of the spaced crests 15 is prevented during movement of the web group in the arcuate portion of its path of travel, misregister of. printed or other patterns on the webs cannot'occur and the slack 1,

of the inner webs W between the regions of the crests 15 cannot atfect the tension in such webs at the runs of the web group leading to or from the arcuate portion of the path defined by cylinder 10. Further, since the inner webs W, are free to bow inwardly into recesses 16 betwee'nt-he regions of crests 15, creasing-or wrinkling of the inner webs will not result from the fact that the outer web W tends to travel a greater distance than the inner webs. 3

Referring now to FIG. 4, it will be seen that a rotary cylinder b forv peripherally defining an arcuate portion of the path of the web group G in accordance with another embodiment of the in'ventionmay include end disks 26 fixed on an axle 27 which is rotatably supported, and a series of small diameter rollers 28 extending axially between disks 26 and being circumferen-tially spaced apart. In the cylinder 10b, the rollers 28 define the ridge elements of the periphery and the sides of the rollers 28 facing away from axle 27 constitute the narrow webengaging crests b of such ridge elements. Further, the gaps or spaces between rollers 28 constitute the recesses 16b 'which'are sufliciently wide and deep topermit inward bowing of the portions of'the inner webs between the regions thereof at the crests of rollers 28.

-When the ridge elements of the rotaryzcylinder are in the form of rollers, as shown on FIG. 4, such rollers 28 are preferably mounted for free rotation about their respective axes and, in that case, the cylinder 10b is positively driven at a peripheral speed difierent from, and preferably greaterthan, the speed of movement of the web group G. For example, the cylinder 10b may be driven at a peripheral speed which is 125 to 150% of the speed at which web group G is drawn through its path. .Where the cylinder-10b replaces the cylinder 10of"FIG. 1,. the

described differential between the peripheral speed of cylinder 10b and the speed at which the web group is drawn by-cylinders 12 and 13 can be achieved either. at the gearing 21 or 23 .or by providing the drive cylinders 12 and 13 with smaller diameters than thecylinder 10b.- It is also apparent that the cylinder 10brnay be positively driven by a variable speed .drive that is: independent of the drive for the cylinders 12 and 13.

.As .a result of the ditference between the peripheral speed of cylinder 10b and thevspeed of movement of the web group G, the rollers 28 roll'along the innermost web of the webgroup in the arcuateportion of the path. If the peripheral speed of cylinder 10b is greater than the web, speed, the rollers 28 turn inthe .directions of the arrows on FIG.- 4 and thus advance'relative to the web group in the direction of movement of the latter. The

Throughout the arcuate portion" of-the the periphery of cylinder 100.

rolling action of rollers 28 against the innermost web of web group G serves to iron out or smooth any creases, bulges or other irregularities present in the webs or that might be formed therein bybearing against the narrow crests of rollers 28.

' Although the rollers 28 roll relative to the web group in the arcuate portion of .thezpath, it will be apparent that, as in the previously described embodimentsfthe narrow web-engagingcrests presented by the sma-lldiameter rollers 28 localize the'pressure of the web :group bearing against them so that .the. friction resultingbetween the webs will keep the webs from slipping longitudinally relative to one another .in the regions of the crests, while the spaces or gaps between the rollers define recesses permitting inward bowing of portions ofthe inner webs between the regions .of the crests.- Thus, ..misregister, loosening of the inner webs .atthe run of the web group leading to cylinder 10b and wrinkling of the inner webs areyall avoided.

Even though the regionsof :the .crests of rollers .28 are .translated relative toithe web group in the arcuate porportion of its path of travel through a web processing machine in accordance with this invention may be part of means by whichthe web group is drivenwor drawn through such path and/ or part of means by which the web group is cut, perforatedor otherwise processed during its continuous movement through such path. For example, FIG. '5 shows a portion of a machine llc whichisgenerally similar to that disclosed in detail in US. Patent No. 3,l74',372,issued March 23, 1965, to W. F. Huck, and

which is intended to cut the continuous web group G into separated sections which are successively delivered during the continuous movement of the web group through a path of travel having an arcuate portion defined by the peripheryvof the-rotary cylinder 10c- .In the machine 11c, cylinder is part of a rotary cuttingmech-anism that further includes a cylinder 29. The cylinders .10c. and 1 29 are journalled, at their ends, in bearings carried by side frame members for rotation about parallel axes which are spaced to provide a zone of tangency between the two cylinders. The cylinder 10c.inclu des a generally cylindrical body carrying equally circumferentially spaced cutting blades or knivesfl'aO suitably secured in axially extending recesses of the. body 190, and thecylinder 29 includes a body 31 carrying elongated anvilmembers 32 which are equal in number to the blades 30 and accommodated in axially extending recesses of body 31. The cylinders 10c and 29 are positively counter-rotated, forexample, in the clock wise and counter-clockwise directions, as shown, so that each blade 30 moves through thezone of tangencybetweenthe cylinders simultaneously with a related one of the anvil members 32 to cooper-ate withthe latter in transversely cutting the web group therebet'ween.

'The web group G is wrapped around a substantial peripheral portion ,of cylinder 100 before reaching the zone of tangency between that cylinder and cylinder 29, and is driven to the zone of tangency by the rotated cylinder10c 'in cooperation with a device 33. The device 33 includes a plurality of belts 34 guided around pulleys 35 and 36 each belt 34 is arcuately wrapped over web group G on Suchfiight 'of each belt 34 is pressed tightly against the Web group on cylinder 100 by tension applied to the belt through a tension pulley37-rotatably supported by arms 38 extending radially from an axle 39 journalled in side frame members17c. vA radial arm 40 extends from axle 39 and is urged in the :clockwise direction, as viewedon FIG. 5, forexample,

by the ram of a :cylinder 41 to which compressed air is suitably supplied, thereby to tension belts 34.

The cylinder 10c-is construc ted,'as disclosed'fully in vU.S. Patent No. 3,174,372, to have a variable effective circumference which may .be adjusted in accordance with 'the actual tension in the web group G in advance of the cylinder so as to maintain a constant tension in the run of the webgroup leading to cylinder 100, or in accordance with deviations from'correct'register of the patterns on the webs with respect to the knives 30 so as .to maintain correct register. In order to have a variable effective circumference, the cylinder 10:: generally comprises bar elements 42 slidably receivedin axially extending, radially opening slots formed at circumferentially spaced locations in the surface of body 19c. Each bar element 42 is of T-shaped cross-section to. include a relatively wide flange or head projecting from the related slot and cooperating with thefl'anges or heads of the other bar elements to form the peripheralstructure of cylinder 10c between knives 30. The radial movements of bar elements 42 for tension or register control areetfected by a mechanism (not shown) as disclosed in US. Patent No. 3,174,372which operates in response totUrning-of an arm 43 by longitudinal displacementof a link 44connected thereto. The link 44' may bedisplaced in accordance with displacements of a floating roller or cylinder (not shown) having a peripheral construction as shown on any of FIGS. 2, 3 and 4, and which-is displaced either in response to deviations of the tension in the web group in advance of cylinder 10c from a predetermined value of tension, or in response to a sensed register error.

In accordance with the present invention, and as shown particularly on FIG. 6, the relatively wide heads or flanges-of bar elements 42 which form the peripheral structure of cylinder 100 between knives 30 have axially extending ridge elements 14c-which are spaced in the circumferential direction to define recesses 16c therebetween and which present narrow web-engaging crests 150. As

in the previously described embodiments of the invention,- the pressure of the web group G bearing against ridge elements 140 is localized at the regions of crests 150 so that the resulting friction between the webs of the group will keep the webs from'sliding longitudinally relative to one another in the regions of the crests. Further, the recesses 160 are sufliciently wide and deep to permit inward bowing of the-portions of the inner webslbetween the regions of the crests c.

Thus, the web group is guided bythe periphery of the driving and cutting cylinder 100 in an arcuate portion of its path without introducing misregister as between the 1 several webs, and without wrinkling of the inner webs register with each other, and folded to form signature strands, whereupon, several signature strands are guided together and collated to form a continuous strand or web group .in which all the book pages are in register with each other.

hen the web group Gis composed of longitudinally ifolded webs or ribbons so that the several superimposed webs or layers are connected at folds extending along one or both longitudinal edges of the web group, the

web group G and rotary cylinder 10 are laterally located I relative to each other so thateach-folded edge F of the web, group extends beyond the ridge elements 14 of the cylinder, forexample, as shown on FIG. 7. Thus, the relativelystif f folded edge F of the web group is free to flex arcuately about any neutral axis that it may adopt,

whereas the remainder oi the web group engaged by ridge elements 14 of cylinder 10 assumes ,the configuration shown on FIG. 2 in moving in the arcuate portion of its path defined by that cylinder.

The employment of a rotary cylinder embodying this invention for driving a web group, as at 10' on FIG. 1, eliminates the wrinkling of the outer webs of a web group that occurs when the latter is driven by passage through the nip of a pair of smooth surfaced driving cylinders.

Although particular embodiments of theinvention have been described in detail herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various changes and modifications may be eifected therein by one skilled in the art without departing from the scope or spirit of the invention, which is intended to "arcuate portionof said vpath, the periphery of said cylinder being defined by ridge elements spacedapart circumferentially and extending axially thereon and engaging the innermost web of the group, said elements presenting webengaging crests sufiiciently narrow to localize the pressure of the web group bearing against them so that the friction resulting between said webs will keep the webs from slipping longitudinally relative to one another in the regions of said crests, said periphery'c'omprising between said elements axial recesses which are sufficiently wide and'deep to permit inward bowing of portions of theinner webs of said web group between said regions. 2. A web processing machine as in claim 1; wherein *said rotary cylinder has a generally cylindrical body and said ridge elements are constituted by ingradially outward from saidbody. I 3. A web processing machine as'in claim 2; wherein each of said axial ribs is of triangular cross-section to axial ribs projectdefine said narrow web-engaging crest at the apex of 'saidcross-se'ction.

' 4. A 'web processing machine as in claim 2; further comprising means removably securing each of said axial ribs to said body so that the ribs can be individually replaced.

5. A web processing machine as in claim 1; wherein said ridge elements are constituted by small diameter rollers which extend axially and are circumferentially spaced apart at the periphery of said cylinder to define said web-engaging crests at the sides of said rollers facing away .from the axis of said cylinder and to define said recesses between the adjacent spaced rollers.

6. A web processing machine as in claim 5; wherein said rollers are individually freely rotatable about their respective axes; and

further comprising means driving said rotary cylinder at a peripheral speed different from the speed at which the web group is drawn through said path so that said rollers roll relative to the innermost web of the group and correspondingly displace said regions of'the crests in the longitudinal direction of the web group in said arcuate portion of its path.

7. A web processing machine as in claim 6; wherein said means driving the rotary cylinder effects rotation of the latter at a peripheral speed greater than said speed at which the web group is drawn through said path.

8. A web' processing machine as in claim 1; wherein said recesses are of a width at least three times greater than the width of said web-engaging crests. I

9. A web processing machine as in claim 1; further comprising means driving said rotary cylinder at a periphzeral speedsubstantially equal to the speed at which the web group is drawn through said path; and wherein said rotary cylinder is part of said means for drawing the web group through said path.

10. A web processing machine as in claim 9; wherein said means for drawing the web group through said path further includes an additional rotary cylinder similar to the first mentioned rotary cylinder and peripherally engaging the web group to guide the web group for a substantial wrap thereof on the periphery of said first rotary cylinder, whereby to ensure positive driving of the web group by said first rotary cylinder.

11. A web processing machine as in claim 10; further comprising means for bodily displacing said additional rotary cylinder relative to said first rotary cylinder, thereby to vary the extent of said wrap of the web group on the periphery of said first rotary cylinder.

12. A web processing machine as in claim 1; wherein the superimposed webs of the web group are joined at folds extending along at least one of the longitudinal edges of the web group, and said folds of the web group extend laterally beyond the adjacent ends of said ridge elements of the rotary cylinder.

13. A web processing machine as in claim 1; further comprising web processing means mounted at the periphery of said rotary cylinder to act on said web group drawn continuously through said arcuate portion of its path.

14. A web processing machine as in claim 1; wherein said cylinder includes a generally cylindrical body, and bar elements extending axially on said body and having said ridge elements projecting radially outward therefrom, said bar elements being movable radially with respect to said body for varying the efiective circumference of the periphery of said rotary cylinder comprised of said ridge elements and said recesses therebetween.

15. A method of transporting a web group composed of a multiplicity of superimposed continuous flexible webs through a path having an arcuate portion in which the individual webs tend to travel different distances, comprising drawing the web group through said path 'under continuous tension, and supporting the web group against movement toward the center of curvature of said arcuate portion of its path only at zones of contact with the innermost web which extend transversely across the web group and are spaced apart along the web groups in said arcuate portion of its path, said zones of contact being sufliciently narrow to localize the pressure of the web group bearing thereagainst by reason of said tension so that the friction resulting between the webs will keep the webs from slipping relative to one another in the regions of said zones of contact and the spacing of the zones of contact being sufiicient to permit inward bowing of portions of the inner webs of said web group between said regions of the zones of contact.

16. A method as in claim 15, and continuously driving said zones of contact along said arcuate portion of said path at the same speed as said web group.

17. A method as in claim 15, and continuously displacing said zones of contact lengthwise of said web group by rolling them along the innermost web of the group in said arcuate portion of said path.

References Cited by the Examiner UNITED STATES PATENTS 1,185,260 5/1916 Stine 226193 X 2,339,557 1/1944 Runals 226l X 2,776,832 1/1957 La ch 226171 M. HENSON WOOD, JR., Primary Examiner. A, N, KNOWLES, Assistant Examiner 

1. IN A WEB PROCESSING MACHINE INCLUDING MEANS FOR DRAWING A WEB GROUP COMPOSED OF A MULTIPLICITY OF CONTINUOUS PATTERNED FLEXIBLE WEBS SUPERIMPOSED IN REGISTER CONTINUOUSLY AND UNDER CONTINUOUS TENSION THROUGH A PATH HAVING AN ARCUATE PORTION IN WHICH THE INDIVIDUAL WEBS TEND TO TRAVEL DIFFERENT DISTANCES, A ROTARY CYLINDER PERIPHERALLY ENGAGING THE WEB GROUP AND DEFINING AND ARCUATE PORTION OF SAID PATH, THE PERIPHERY OF SAID CYLINDER BEING DEFINED BY RIDGE ELEMENTS SPACED APART CIRCUMFERENTIALLY AND EXTENDING AXIALLY THEREON AND ENGAGING THE INNERMOST WEB OF THE GROUP, SAID ELEMENTS PRESENTING WEBENGAGING CRESTS SUFFICIENTLY NARROW TO LOCALIZE THE PRESSURE OF THE WEB GROUP BEARING AGAINST THEM SO THAT THE FRICTION RESULTING BETWEEN SAID WEBS WILL KEEP THE WEBS FROM SLIPPING LONGITUDINALLY RELATIVE TO ONE ANOTHER IN THE REGIONS OF SAID CRESTS, SAID PERIPHERY COMPRISING BETWEEN SAID ELEMENTS AXIAL RECESSES WHICH ARE SUFFICIENTLY WIDE AND DEEP TO PERMIT INWARD BOWING OF PORTIONS OF THE INNER WEBS OF SAID WEB GROUP BETWEEN SAID REGIONS. 